02-02-2012
If you'd bothered posting your /proc/cpuinfo, I might be able to explain, but at present I can only guess.
Do your CPU's have hyperthreading? That will show up as double the number of cores in Linux.
10 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
Is there an easy way in Solaris to count the number of processors? (2 Replies)
Discussion started by: hshapiro
2 Replies
2. UNIX for Dummies Questions & Answers
hi,
i want to know cpu utilizatiion per process per cpu..for single processor also if multicore in linux ..to use these values in shell script to kill processes exceeding cpu utilization.ps (pcpu) command does not give exact values..top does not give persistant values..psstat,vmstat..does njot... (3 Replies)
Discussion started by: pankajd
3 Replies
3. Solaris
Hello Friends,
On one of my Solaris 10 box, CPU usage shows 100% using "sar", "vmstat". However, it has 4 CPUs and prstat and glance are not showing enough processes to justify high CPU utilization.
=========================================================================
$ prstat -a
... (4 Replies)
Discussion started by: mahive
4 Replies
4. Solaris
Can anyone tell me difference between cpu-shares vs cpu-cap in solaris & how FSS will work with cpu-caps ? (9 Replies)
Discussion started by: fugitive
9 Replies
5. UNIX for Dummies Questions & Answers
We have purchased four intels xeon processors
Intel® Xeon® Processor E7530 (12M Cache, 1.86 GHz, 5.86 GT/s Intel® QPI) with SPEC Code(s) SLBRJ
As per the specification each cpu has 6 cores therefore we have 24 cores (considering 4 cpus).
Now how would i calculate the number of vcpus that can... (1 Reply)
Discussion started by: pinga123
1 Replies
6. AIX
I have a number of LPARs on one P520. All LPARs are running 5.3 and I observe the following:
On some LPARs the number of CPUs found do not match between topas and mpstat.
Server 1:
$ mpstat
System configuration: lcpu=4 ent=0.2 mode=Uncapped
cpu min maj mpc int cs ics rq ... (1 Reply)
Discussion started by: petervg
1 Replies
7. Red Hat
Hello,
sysinfo throws out below 3 CPU counts. Can anyone help me understand what each of these means?
CPU Count Socketed is 2
CPU Count Physical is 8
CPU Count Virtual is 16
First one seems obvious. However, I wonder how there can be 8 Physical CPUs, if... (2 Replies)
Discussion started by: hnhegde
2 Replies
8. UNIX for Dummies Questions & Answers
We have a single threaded application which is restricted by CPU usage even though there are multiple CPUs on the server, hence leading to significant performance issues. Is it possible to merge / combine multiple CPUs at OS level so it appear as a single CPU for the application? (6 Replies)
Discussion started by: Dissa
6 Replies
9. AIX
seeing weirdness across some 7.1.5.1 LPARs - they all have 2 vCPUs allocated shared. With prtconf they show 2 CPUs, 'lsdev -c processor' concurs, and 'lsattr -El procX' shows that SMT is enabled and there are 2 SMT threads (power5, sorry). Yet running topas on them shows 2 CPUs on some and 4 on... (3 Replies)
Discussion started by: maraixadm
3 Replies
10. UNIX for Beginners Questions & Answers
I read that Entitlement CPU should be set to max 75% compare to Virtual CPU. May I know the reason.
I have set the Entitlement CPU = Virtual CPU on AIX . It works fine .
Can you help to understand. (1 Reply)
Discussion started by: gabhanes
1 Replies
LEARN ABOUT DEBIAN
cpulimit
CPULIMIT(1) User commands CPULIMIT(1)
NAME
cpulimit -- limits the CPU usage of a process
SYNOPSIS
cpulimit [TARGET] [OPTIONS...]
DESCRIPTION
TARGET must be exactly one of these:
-p, --pid=N
pid of the process
-e, --exe=FILE
name of the executable program file
-P, --path=PATH
absolute path name of the executable program file
OPTIONS
-b, --background
run cpulimit in the background, freeing up the terminal
-c, --cpu
specify the number of CPU cores available. Usually this is detected for us.
-l, --limit=N
percentage of CPU allowed from 1 up. Usually 1 - 100, but can be higher on multi-core CPUs. (mandatory)
-v, --verbose
show control statistics
-z, --lazy
exit if there is no suitable target process, or if it dies
-h, --help
display this help and exit
EXAMPLES
Assuming you have started `foo --bar` and you find out with top(1) or ps(1) that this process uses all your CPU time you can either
# cpulimit -e foo -l 50
limits the CPU usage of the process by acting on the executable program file (note: the argument "--bar" is omitted)
# cpulimit -p 1234 -l 50
limits the CPU usage of the process by acting on its PID, as shown by ps(1)
# cpulimit -P /usr/bin/foo -l 50
same as -e but uses the absolute path name
# /usr/bin/someapp
# cpulimit -p $! -l 25 -b
Useful for scripts where you want to throttle the last command run.
# cpulimit -l 20 firefox
Launch Firefox web browser and limit its CPU usage to 20%
# cpulimit -c 2 -p 12345 -l 25
The -c flag sets the number of CPU cores the program thinks are available. Usually this is detected for us, but can be over-ridden.
NOTES
o cpulimit always sends the SIGSTOP and SIGCONT signals to a process, both to verify that it can control it and to limit the average
amount of CPU it consumes. This can result in misleading (annoying) job control messages that indicate that the job has been stopped
(when actually it was, but immediately restarted). This can also cause issues with interactive shells that detect or otherwise depend
on SIGSTOP/SIGCONT. For example, you may place a job in the foreground, only to see it immediately stopped and restarted in the back-
ground. (See also <http://bugs.debian.org/558763>.)
o When invoked with the -e or -P options, cpulimit looks for any process under /proc with a name that matches the process name argument
given. Furthermore, it uses the first instance of the process found. To control a specific instance of a process, use the -p option
and provide a PID.
o The current version of cpulimit assumes the kernel HZ value 100.
AUTHOR
This manpage was written for the Debian project by gregor herrmann <gregoa@debian.org> but may be used by others.
cpulimit June 2012 CPULIMIT(1)